Career Summary

Biography

Research Expertise
I am a synthetic organic chemist with 10 publications and two international patents in the areas of conducting polymers, organic photovoltaic devices and the development of new materials for inclusion into these devices and have been responsible for the establishment of successful multidisciplinary collaborations with Nobel Laureate and conducting polymer chemist Prof. Alan MacDiarmid and physicist A/Prof. Paul Dastoor in areas directly applicable to this application.
The patent held in conjunction with Prof. MacDiarmid, covers the preparation and processing of conducting polymers, a major consideration in the use of these materials in organic devices where often costly and time consuming methods are required. This contribution led to my employment in 2005 with A/Prof. Dastoor at the University of Newcastle studying the effect of incorporating porphyrin dye materials into conventional organic photovoltaic devices. This research has significantly improved the understanding of how devices of this type function. The work led to a patent covering the fabrication of multicomponent organic photovoltaic devices of the type which will be built and examined within this project and has highlighted the critical need to control the morphology of materials within these devices if significant advances are to be made in efficiency. As a result I have recently become active in the development and use of Scanning Transmission X-Ray Microscopy (STXM), Near-field Scanning Photocurrent Microscopy (NSPM) and other techniques to study the morphology of materials and relate this characteristic to key properties such as charge mobility and photocurrent generation within them. Utilising the expertise and skills developed in these studies I am now developing new organic field effect transistors for use as biosensors and extending my understanding of these materials to organoelectronics in general. The current project is the logical extension of my career to date, recognising the need to control the morphology of the materials within organoelectronic devices and directly addressing this need.
Recognition of my contribution to the field came at the beginning of 2007 when I was appointed as a lecturer in chemistry at the University of Newcastle within the new Priority Research Centre for Organic Electronics.

Teaching Expertise
During my years working I have developed experience teaching chemistry at up to 3000 level, in particular at Massey University where I developed and taught the 123:318 Advanced NMR Spectroscopy course for three years (12 lectures and associated labs and tutorials, 2002-4) and undertook relief teaching for 123:314 Physical Chemistry. At various times, when required, I taught Organic Chemistry, Inorganic Chemistry and a 4000 level Supramolecular Chemistry course.
In my current position as Lecturer of Chemistry at the University of Newcastle I am teaching into the 2nd year Organic Chemistry course (CHEM2310), 3rd year Molecular Organic Synthesis (CHEM3310) and 3rd year Environmental Chemistry (CHEM3610).

Qualifications

PhD, University of Auckland - NZ

Bachelor of Science, University of Auckland - NZ

Master of Science, University of Auckland - NZ

Keywords

Conducting Polymers

Materials Science

Organic Chemistry

OrganoElectronics

Porphyrins

Fields of Research

Code

Description

Percentage

020499

Condensed Matter Physics not elsewhere classified

40

030304

Physical Chemistry of Materials

35

030699

Physical Chemistry not elsewhere classified

25

Professional Experience

UON Appointment

Title

Organisation / Department

Research Associate

University of NewcastleSchool of Mathematical and Physical SciencesAustralia

Abstract Scanning transmission X-ray microscopy (STXM) compositional mapping has been used to probe the mesomorphology of nanoparticles (NPs) synthesized from two very different p... [more]

Abstract Scanning transmission X-ray microscopy (STXM) compositional mapping has been used to probe the mesomorphology of nanoparticles (NPs) synthesized from two very different polymer:fullerene blends: poly(3-hexylthiophene) (P3HT): phenyl-C61-butyric acid methyl ester (PCBM) and poly[4,8-bis(2-ethylhexyloxy)benzo(1,2-b:4,5-b')dithiophene-alt-5, 6-bis(octyloxy)-4,7-di(thiophen-2-yl)(2,1,3-benzothiadiazole)-5,5'-diyl] (PSBTBT): PCBM. The STXM data shows that both blends form core-shell NP structures with similar shell compositions, but with different polymer:fullerene ratios in the core regions. P3HT:PCBM and PSBTBT:PCBM NP organic photovoltaic (OPV) devices have been fabricated and exhibit similar device efficiencies, despite the PSBTBT being a much higher performing low band gap material. By comparing the measured NP shell and core compositions with the optimized bulk hetero-junction (BHJ) compositions, we show that the relatively higher performance of the P3HT:PCBM NP device arises from the fact that its shell composition is much closer to the optimal BHJ value than that of the PSBTBT:PCBM NP device.

Here, we report the development of an organic thin film transistor (OTFT) based on printable solution processed polymers and employing a quantum tunnelling composite material as a... [more]

Here, we report the development of an organic thin film transistor (OTFT) based on printable solution processed polymers and employing a quantum tunnelling composite material as a sensor to convert the pressure wave output from detonation transmission tubing (shock tube) into an inherently amplified electronic signal for explosives initiation. The organic electronic detector allows detection of the signal in a low voltage operating range, an essential feature for sites employing live ordinances that is not provided by conventional electronic devices. We show that a 30-fold change in detector response is possible using the presented detector assembly. Degradation of the OTFT response with both time and repeated voltage scans was characterised, and device lifetime is shown to be consistent with the requirements for on-site printing and usage. The integration of a low cost organic electronic detector with inexpensive shock tube transmission fuse presents attractive avenues for the development of cheap and simple assemblies for precisely timed initiation of explosive chains.

The impact of a calcium interface layer in combination with a thermal annealing treatment on the performance of poly(3-hexylthiophene) (P3HT):[6,6]-phenyl-C61-buteric acid methyle... [more]

The impact of a calcium interface layer in combination with a thermal annealing treatment on the performance of poly(3-hexylthiophene) (P3HT):[6,6]-phenyl-C61-buteric acid methylester (PCBM) nanoparticle photovoltaic devices is investigated. Annealing is found to disrupt the microstructure of the nanoparticle active layer leading to a reduction in fill factor. However, X-ray photoelectron spectroscopy measurements show that the calcium interface layer causes PCBM to preferentially migrate to the cathode interface upon annealing, resulting in better charge extraction from the PCBM moiety, an increase in the built-in voltage, open-circuit voltage, and power conversion efficiency. Moreover, the annealing trends could be completely explained by the observed PCBM migration. Unlike P3HT:PCBM bulk heterojunction devices, the P3HT:PCBM nanoparticle devices showed a remarkable thermal stability up to 120Â°C. As such, OPVs fabricated from aqueous nanoparticle inks provide an attractive alternative to conventional organic solvent based bulk heterojunction devices.

We present a dynamic Monte Carlo (DMC) study of s-shaped current-voltage (I-V) behaviour in organic solar cells. This anomalous behaviour causes a substantial decrease in fill factor and thus power conversion efficiency. We show that this s-shaped behaviour is induced by charge traps that are located at the electrode interface rather than in the bulk of the active layer, and that the anomaly becomes more pronounced with increasing trap depth or density. Furthermore, the s-shape anomaly is correlated with interface recombination, but not bulk recombination, thus highlighting the importance of controlling the electrode interface. While thermal annealing is known to remove the s-shape anomaly, the reason has been not clear, since these treatments induce multiple simultaneous changes to the organic solar cell structure. The DMC modelling indicates that it is the removal of aluminium clusters at the electrode, which act as charge traps, that removes the anomalous I-V behaviour. Finally, this work shows that the s-shape becomes less pronounced with increasing electron-hole recombination rate; suggesting that efficient organic photovoltaic material systems are more susceptible to these electrode interface effects.

Abouderbala LO, Belcher WJ, Boutelle MG, 'Cooperative anion binding and electrochemical sensing by modular podands', PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 99 5001-5006 (2002) [C1]